The gyrfalcon ( or ) (), the largest of the falcon species, is a bird of prey. The abbreviation gyr is also used. It breeds on Arctic coasts and tundra, and the islands of northern North America and the Eurosiberian region. It is mainly a resident there also, but some gyrfalcons disperse more widely after the breeding season, or in winter. Individual vagrancy can take birds for long distances. Its plumage varies with location, with birds being coloured from all-white to dark brown. These colour variations are called morphs. Like other falcons, it shows sexual dimorphism, with the female much larger than the male. For centuries, the gyrfalcon has been valued as a hunting bird. Typical prey includes the ptarmigan and waterfowl, which it may take in flight; it also takes fish and mammals. Taxonomy and etymology The gyrfalcon was formally described by Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under its current binomial name Falco rusticolus. The genus name is the Late Latin term for a falcon, , from a sickle, referencing the talons of the bird. The species name is from the Latin , a countryside-dweller, from , "country" and , "to dwell". The bird's common name comes from French ; in Medieval Latin, it is . The first part of the word may come from Old High German ( modern German ; ultimately from Proto-Germanic ("greed")) for "vulture", referring to its size compared to other falcons; or from the Latin for "circle" or "curved path", in turn from the Ancient Greek , , meaning "circle" – from the species' circling as it searches for prey, distinct from the hunting of other falcons in its range. The male gyrfalcon is called a gyrkin in falconry. Description The gyrfalcon is the largest falcon in the world, being about the same size as the largest buteos (buzzards) but probably slightly heavier. Males are long, weigh , with average weights reported as and have a wingspan from . Females are bulkier and larger, at long, wingspan, and of weight, with average weights of . An outsized female from eastern Siberia was found to have scaled . Among standard measurements, the wing chord is , the tail is , the culmen is and the tarsus is . The gyrfalcon is larger, broader-winged and longer-tailed than the peregrine falcon, which it is known to compete with